888-19-7Relevant articles and documents
Transition-Metal-Free Deconstructive Lactamization of Piperidines
Romero-Iba?ez, Julio,Cruz-Gregorio, Silvano,Sandoval-Lira, Jacinto,Hernández-Pérez, Julio M.,Quintero, Leticia,Sartillo-Piscil, Fernando
, p. 8867 - 8871 (2019/05/28)
One of the major challenges in organic synthesis is the activation or deconstructive functionalization of unreactive C(sp3)–C(sp3) bonds, which requires using transition or precious metal catalysts. We present here an alternative: the deconstructive lactamization of piperidines without using transition metal catalysts. To this end, we use 3-alkoxyamino-2-piperidones, which were prepared from piperidines through a dual C(sp3)–H oxidation, as transitory intermediates. Experimental and theoretical studies confirm that this unprecedented lactamization occurs in a tandem manner involving an oxidative deamination of 3-alkoxyamino-2-piperidones to 3-keto-2-piperidones, followed by a regioselective Baeyer–Villiger oxidation to give N-carboxyanhydride intermediates, which finally undergo a spontaneous and concerted decarboxylative intramolecular translactamization.
New bis-indolic macrolactams
Henin,Noe,Laronze
, p. 1693 - 1703 (2007/10/03)
Treatment of several ω-halogenoamides, derived from tryptamine, with powdered potassium hydroxide in 1,2-dimethoxyethane in the presence of 18-crown-6, resulted in intramolecular and/or bimolecular cyclization, depending on the length of the chain and dilution conditions, to give macrocyclic compounds. Some of them were converted by a Bischler-Napieralski reaction, followed or not by reduction, to new tetracyclic derivatives of β-carbolines.